The objective of this project is the research and development of analytical techniques which are used to: (1) Establish the structure and purity of new antitumor agents and their metabolites, (2) determine physical and chemical properties of new anticancer drugs and (3) study reaction mechanisms. Mass spectrometry, gas-liquid chromatography and the combination of these techniques is emphasized. Compounds of current interest are 5-azacytidine, reduced nucleosides, hydantoins, and aziridinylquinones. Silation mediated oxidation reactions are under investigation.